Senator Barbara Mikulski, the longest-serving female senator in U.S. history, on Monday announced that she will retire at the end of her term, setting up a contest among possible successors in the heavily Democratic state of Maryland.

The top Democrat on the powerful Senate Appropriations Committee, Mikulski, 78, told reporters in Baltimore that she would serve out her remaining two years in office. She has served in Congress for nearly 40 years.

Unlike other departing lawmakers, Mikulski said she was not disillusioned with what many see as a dysfunctional legislative body, nor is she suffering from any health issues.

She said she still relished the fight and planned to keep pushing the Democratic agenda on jobs, federal funding and other issues until her term ends in late 2016.

“For the next two years, I will be here, working the way I do, 100 percent, fighting the way I do,” she said.

She said she did not want to spend the last years of her career campaigning for re-election. “Do I spend my time raising money, or do I spend my time raising hell?” she said.

In the Senate since 1987, and before that in the U.S. House of Representatives for 10 years, the Baltimorean earned a reputation for toughness and fiery rhetoric, and for steering government money to her state.

Possible contenders to replace her could include Chris van Hollen or Elijah Cummings, who are among Maryland Democrats in the House of Representatives.

Former Maryland Governor Martin O’Malley, who left office in January, could be in contention. The surprise loss of his former lieutenant governor, Anthony Brown, to a Republican in the November gubernatorial election could be an issue, however.

Mikulski declined to comment on possible replacements.

One of the more liberal members of Congress, Mikulski opposed the 2003 invasion of Iraq and defended government spending in an era of austerity, saying in 2012 that Congress could be “frugal without being heartless.”

In 2012, when NASA researchers in Baltimore discovered the fleeting glimmer of an exploding star, they named it “Supernova Mikulski,” after one of their chief congressional patrons.

(Reporting by Emily Stephenson and David Lawder; Editing by Kevin Drawbaugh, Bill Trott and David Gregorio)